CtrlShiftT
by Frozest
Summary: Adopted!g!pElsa and Anna become sisters with benefits after Anna is caught browsing Elsanna nsfw's. Very smutty. Much incest. (Cover art by muuuuug on Tumblr.)
1. Regrets Like Flappy Bird

_Holy shit._

_Like, what? Holy- holy shit._

_Wow…that's…okay that's-_

"Anna?" A light tap on my door followed my older sister's voice. "What are you doing? Are you thinking aloud again?"

I paused briefly from recollecting the stapler, pens, and papers that flew off my desk as a result of my graceless reaction. "Maaaybe," I hummed before frantically starting to muddle rather than tidy as Elsa stepped through my door.

Elsa began to ask again, but her words trailed into silence once her eye caught sight of-

"**Shoot**." My pinkie slammed down on the Ctrl key as my middle finger stretched over to W. That was close.

I was going to turn back to face her and answer the question that inevitably hung from her lips, but her arms laced themselves around my freckled shoulders before I could speak. And suddenly, I couldn't. I had never heard such husky growl in her voice than when she whispered, "What was that?"

"Fuck," I mumbled as I noticed she distracted me just enough to reopen the tab.

She giggled, "That's what I thought."

Right about now would be the point at which I started regretting having not put on a bra this morning. The only thing covered my torso was an old, stained camisole. Cami and I shared many a nights together. It was the most comfortable thing I owned.

But right about now I couldn't have regretted wearing it any less than I regret downloading Flappy Bird. The fucking thing. My nipples were poking right through the thin, tight fabric, and Elsa didn't take her time noticing. Her hand slipped down into my shirt and pressed hard against the skin above my left boob. "You're so cute, Anna."

I swallowed hard. My voice nearly breaking, "Move your hand."

"You heart is racing." She ground my ear lobe between her teeth, "Where are your manners?"

"…p-please," I stuttered. Why did I stutter? This felt wrong. No, this _was_ wrong.

Her hand moved, finally, bu- but in the wrong direction. It slinked its way down deeper into my shirt until her soft fingertips massaged my hard nipple. Elsa's lips pecked at my bare shoulder endlessly until she paused enough to howl out, "Better?"

I moaned, dammit, choking down all the words of praise and all the cries in denial because I couldn't decide which were the lies anymore.

Cami was on the floor. Elsa was in my lap. Her tongue was in my mouth and I still had no idea what was going on.

I knew I was breathing heavy, but I didn't know why.

I knew _she_ was getting me hotter, but I didn't get how.

I knew I wanted something, but I didn't know…what.

Until it hit me. Elsa's hand in my pants. Her finger inside of me. Her tongue unable to decide if it wants to massage mine or my ever-hardening nipples. The overall rush of being wanted- needed. It was the rush of being loved in a way I could never have been by anyone else. I realized, I wanted _her._

So I let my inhibitions go, and moaned, and replied, "Much."


	2. It's A Date

I was still reeling in my spinny desk chair when the door shut behind a smugly grinning older sister of mine. "Fuck….did that just happen?"

My breaths were horribly broken and desperate. I think I was trembling. Every muscle in my body was goo in my chair. That was, by far, the best fuck I've ever had. Or was it the _worst_? I was so tired it was an easy couple of hours before my text tone nearly threw me out of my chair. The fricking thing gave me a heart attack.

**MOM: "**Dinner"

You gotta love the family phone plan.

I threw on a hoodie from a pile of clothes, taking a whiff of it before I made it all the way downstairs. It wasn't _horrible. _But yeah it was pretty bad. Oh well. It'd be a good Elsa repellant.

that, or a very good reason for her to tear it off my body and leave behind another ravished pile of goo

The first thing I heard when I made it down was my mother saying, "...so you'll be on your own tomorrow night, Elsa."

"That's fine," my older sister replied.

"There's some frozen dinners in the freezer and ramen in the pantry if you're not up to cooking."

"Mkay," she mumbled before setting down her phone beside her plate.

I spooned some rice onto my plate. "Wait, why will Elsa be on her own?"

"Your mother and I are going out for an early anniversary dinner."

"I have a meeting for work the night of our anniversary, but you'll be fine, Anna. You're going out with Krystal that night."

"Actually," I winced, "that date got cancelled."

"How come?" Elsa poked around her plate like it was my brain.

I sat down at my place at the table with a full plate. "She keeps reblogging whiny word pictures on her Tumblr about how she misses Sven."

"What?"

I think I just confused her more.

I gestured outwards with my fork flying freely through the air, "I mean she's never said it _was_ about him but they did date for like two and a half years and broke up like three weeks ago. I think she just needs some time to decide whether she wants to move on or not."

"So it's just you and me tomorrow night," Elsa asked strangely.

When I looked up at her to say, "yup," she gave me a wink that could have knocked me from my chair.

"Uh-huh," I said instead with a dazed and dumbass tone.

"I'll make us something tasty, then."

_Damn, was that an innuendo?_

"Great," I replied in a rush. My voice lined with worry. From then I managed to nonchalantly inhale the rest of my dinner before running up to my room to think.

I couldn't believe my knuckles when they made contact with Elsa's door. Or when my hand when it didn't wait for an answer before turning the handle. Not even my tongue when it spoke.

"Elsa…?" I poked my head in to find a very intent older sister of mine looking up from her laptop and at me. She fidgeted slightly on her bed, but didn't speak. I forced myself inside and leaned up against her now closed door, still gripping the handle tightly. "A- are we going to talk about this?"

"Hm?"

"What happened this afternoon," I clarified.

Elsa's head tilted slightly. It was guiltily cute. "We could."

She sounded so _cool_ about this it threw me off even more. "Um…well…we're _siblings_, and- **that** happened- and, well-"

Elsa set her laptop beside her on the bed and scooched herself forward until her legs hung over the side. "You didn't like it? I mean, it's not the first time I've caught you looking at fanart of us or reading smut. I just _assumed_…" Her voice drifted into its usual timidity as she hugged herself nervously.

"No, no, I mean that was-"

_Shit fuck no don't say that_

_Bad idea back it up back it up say something else_

I couldn't think of how to recoil, but I couldn't stand watching Elsa relapse back into her old conceal-don't-feel self, so in seconds I was sitting beside her on her bed. My hand pried Elsa from herself enough to take her chilly hand. "If I may be damn straight with you," my hand underlined my speech for emphasis, "that was the best sex I have ever had."

_Bloody fucking hell so much for backing it up. Smooth, Anna. Real smooth._

Elsa didn't speak, but she did finally look up at me. Shock. Shock was all I saw.

That is until my eyes caught sight of her pants. _God damn it if she were any harder her zipper would burst._

"So…what does that mean…for us?" She hesitantly began.

"Um….I don't know." I stood and began to pace. I could tell this was eating her just as much as it was eating me.

I think she was ready to burst or jump me or collapse or maybe all three if that was even possible. "Let's just say it meant nothing and forget it?"

"Right, right, sounds great." I moved my limbs in a way that was less a direction than a catastrophe towards the hall. The air must have been poisoned because my breaths fell desperate and neared hyperventilation.

_What the hell is wrong with me?_

But she never opened her door. She never said a word. I stayed there trying to calm my thoughts, breaths, and the trepidation that consumed my being. Once I was able to crawl back into my room, I lied flat on my floor until my tears subsided. My eyes, heavy with sleep, drifted to the digital clock at my bedside. It was 8:41.

_How much homework do I have? Too damn much, as usual. _I hated Sunday nights.

My body jerked itself awake at 3:33 after my average seven hours of sleep. That's when I finally started caring about my homework. Not the best of times to, but hey, it was better than handing it in late…sort of.

I was able to concentrate for about zero minutes before the nagging thought of Elsa hauled me back to her door. She had left it a crack open. I crept inside. Her sheets were thrown back in the shape of her and her bed left empty. I sat on her mattress until the scent of her reeled my head into her pillow, encapsulating the very essence of her through my nostrils.

She always smelled so damn good. Men's cologne was my weakness and she knew it. I swear she wore a heavy amount just so she could drive me crazy from two rooms away.

My body sunk into the bed, and before long I began to doze off. "Anna?" is what threw me upright and awake again. In the doorway stood a figure clothed in nothing but boxers and an extra large shirt. "I- I've been looking for you."

"I was in my room."

"I checked there first, and then the whole rest of the house."

"I didn't pass you on my way here."

"I used the bathroom first."

"Oh…"

"…Did you need something?"

"Yes, but I doubt it's any different from what you were going to say."

"Well, what were you going to say?"

I stood. "Elsa, I-…I can't forget what happened. I just can't."

"Me either," she admitted.

"Soooooo…?" I hoped she'd fill in the enormous blank.

"So do you want to do it again? Maybe…? Sometime?"

"More than anything," I answered breathlessly.

Elsa used her foot to shut her door without looking away from me for a second. "Then let's get these clothes out of the way," she said, tugging my shirt up.

I panicked. "Actually," I said as I pulled my shirt down, "I have a lot of math homework to do before school starts tomorrow- er- today."

"Oh-" she said awkwardly, "okay. That's fine. It's good to prioritize."

I took hold of the door handle, turning it as my free hand intentionally brushed against the fabric of her boxers. "Goodnight."

And I was almost pleased with myself when she couldn't reply before I shut the door behind me.


	3. Yeah, Was All She Said

Elsa and I waved goodbye as our parents shut the door behind them. As soon as it clicked, she spoke. "You sure you want to do this?"

"God, yes."

"We're sisters, remember."

"_You're_ adopted, remember."

"Still." She stood her ground.

So I stood mine, "Still."

"Don't think I don't notice."

"What," she asked right before I slipped my left hand into her right back pocket and went from standing at her side to standing face-to-face.

"The cologne, the winks, the looks," I said all as I slid my right hand down her back and into her left back pocket. I groped her ass tight, pulling her hips into mine. My lips leaned in to her ear and growled, "How hard you are." Her earlobe was caught between my teeth, and the slightest of startled whimpers tumbled from Elsa's lips. How cute.

"Bedroom, now," she demanded.

"That's more like it," I said before I scooped her up in my arms and rushed up the stairs.

I brought her into my room, where it all began, and set her on the bed, quickly following after. My knees were on either side of her hips with our fingers intertwined, forcing half my weight onto her hands, pinning her down. I didn't want her going anywhere. Not yet.

My lips sweetly found hers and kissed softly. I could almost taste the cologne she bathed in this morning. I hovered over her, my heart already racing. "You taste even better than you smell." My teeth tugged on her bottom lip, begging her to open up. I wanted to taste all of her, and this is where it would start.

"No, Anna. Not like this," she said in an alarmingly troubled voice.

I took the pressure off her hands, letting her prop herself on her elbows. Her breaths were heavy, her pupils were dilated.

She flipped me over onto my back. A devilish grin on her face. I could kiss it, but now she had me pinned.

I scowled, almost pleased with her. "You lil' shit."

"We both know you're stronger."

My eyebrow raised playfully. "So how is pinning me down going to stop me?"

"It can't."

"Damn straight."

"But it will," she said as she lowered onto my lips.

"Damn straight," I repeated before she swallowed me whole in a kiss. Her tongue was already so deep in my throat. That's when I realized how desperate she was. This all began because _she_ fucked _me._ I hadn't returned the favor, and it wasn't hard to tell how badly she wanted this.

I slipped my wrists out from underneath her hands without resistance. My older sis trusted I had all the best intentions. And oh, did I.

I stopped at her breasts, groping roughly. Giving her all the permission she needed to get wild. Her tongue left my mouth and met my jaw, not bothering to keep quiet. She sloppily kissed me all over, slipping up my shirt, slipping up my bra. My body sunk into her kisses. My voice hardly came, "E-Elsa-" I stuttered, my hands found her ass, groping hard as I did before. Pulling her bulge into me as I did before. "Please," I unbuttoned and unzipped her pants, "let me return the favor."

She complied, lifting herself up and sitting against the wall, her legs spread and head turned away in embarrassment. I slipped off her jeans, kissing the inside of her thighs and gliding my hands down her sides. She moaned. Oh god. Her moan. It made me want to join in. "You're so adorable," I teased, slipping my fingers underneath the elastic of her boxers. "I wonder how loud I can get you to scream."

I eased her boxers down painfully slow. She tried to yank them off so I'd get down to it already, but I tantalized her, "Ah ah ah, don't make me put those pretty little wrists in handcuffs." Her index finger brushed my nose. She was so cute, I had to giggle as I nibbled on it. After I let go, she pressed her palms into the mattress and gripped the sheets. "Good girl."

With hardly any patience, I surrounded her thick cock with my lips, taking it deep into my throat from the very start. I rolled my tongue around her length as I fucked her slow. I watched her writhe as her body trembled and her fists grip tightened around the sheets. Her eyebrows furrowed and she let out the tiniest wince that made me want to go faster and suck harder.

So I did.

In seconds she was moaning and crying. Her fingers intertwined with my hair and pushed herself deeper down my throat. My left hand found its way to her chest, pinching her nipple and rolling her breast through her shirt until she was so very close to climaxing. Then I stopped.

"Anna," she begged. "No please, Anna, don't stop now. Please…" she forced my hand to grope her breast. She was desperate, and it was adorable.

So I got up. I ripped my jeans off and pulled my bra and shirt over my head. I couldn't take my teasing much longer, either. I needed her. Meanwhile, she had stripped herself completely, too. Now both of us were bare and eagerly taking in every sight of each other's curves. I grabbed her wrists, pinning her to the wall and kissing her rough. I wanted her to taste herself, to know how delicious she was. My right forearm held both her wrists against the wall as my lips never faltered from hers. I pulled her closer from her neck, thrusting my tongue deeper down her throat. Our nipples brushed against each other and sent waves of sensation down my spine. And finally, my hand reached for her cock, gripping at its base. Before she had time to realize it, she was inside of me. I sat in her lap and on her cock, unprepared for how deeply it fucked me and how thick she was against my walls. I felt like exploding. My head rested on her shoulder; I breathed heavy down her chest. "Oh my god," was all I could think to say.

"Let me-" she began.

"No," I said. "I will. It's just- you're so big."

"You like me inside of you."

"So fucking much," I said, laughing in disbelief.

I slammed into her lips once more before gliding up on her cock and back down ever so cautiously. _How can something this great be wrong? _I thrust her inside of me again. _It feels too right. _I thrust her once more inside.

_Damn…I think I'm in love._

The gentleness in me was gone. I fucked her rough and hard. My body slammed hers against the wall. We were making the noisiest of love. Her nails dug into my back as my hands grasped tightly what they could of her beautiful blonde hair.

"Fuck, Anna, fuck fuck fuck fuck fUCK," she screamed. But I wasn't about to slow down. I was close. "Oh god, Anna, I'm going to come." And so was she.

"Fucking come inside of me, Elsa. I want to your hot cum inside of me."

She screamed and came inside, but I never stopped. I wouldn't let this orgasm down easy. I rode her cock fast and hard as she came and writhed and screamed beneath me until I came too, all over her dick which lay deep inside of me. My head fell to her shoulders.

"Fuck," was all I said.

"Yeah," was all she said.


	4. The Aftermath

At least, that's all she said until the caught her breath. Her cock still laid deep inside of me minutes after. "Anna," she began, her voice soft, "what did we just do?"

I kissed her neck sweetly. "Made love."

As soon as Elsa began to squirm, I fell into a panic. When I pulled her out of me, her worried eyes poured into mine. "I think we made a mistake." I didn't reply. I couldn't. I'm fairly certain I had just fallen in love with the way my sister fucks me and she's backing out.

Elsa scooched her way off the bed and grabbed her pants. "This is wrong," she said, slipping one leg on at a time. "We're _sisters_." The blonde fastened her belt. "I should have listened to my gut." She threw on her shirt and headed to the door. "We have to swear to each other that this will never happen again."

My lips wrenched in. I slowly nodded my head and choked back a tear.

"I'm sorry. I really am. I shouldn't have led you on like that." She furrowed her eyebrows and smiled tenderly from my doorway. "Are you okay?"

"Yeah," my hoarse voice trembled out.

I caught the kiss my adorable sister blew and held it, smiling as she left.

Once the door clicked, I pressed her kiss to my lips. My body collapsed onto my mussed sheets, unable to move or speak. Only cry with every inhale I took in Elsa's scent.

I still felt the remains of our love boiling inside of me. She was a part of me now. A part of me I wasn't willing to let go.


End file.
